1. Field
The present invention relates to an electronic device, and more particularly, to a test device for testing a plurality of samples, and an operating method thereof.
2. Discussion of Related Art
Every electronic good currently include various electronic devices. The electronic good needs to meet a predetermined level of reliability or higher. The reliability means whether a sample performs a demanded function under a given condition for a given period. Here, the sample may be any one among various elements forming the electronic good, and includes, for example, an individual element, a function unit, a component, a device, a sub system, and a system.
A reliability test of an electronic device is performed according to a type of tested sample. For example, a condition and a reference of the test may be changed according to whether a type of device sample is a Field Effect Transistor (FET) and a Bipolar Junction Transistor (BJT), or whether a device sample is based on Si or a compound, such as GaAs, InP, and GaN.
The reliability test of the electronic device may be divided into a test applying bias and a test applying no bias, and the test is performed with a predetermined number or more of multi samples in order to have a statistical meaning during the test.
In a case of the test applying the bias, a test condition for the same type of samples is determined considering an upper limit and a lower limit of a condition under which the device is destructed, and an upper limit and a lower limit of a condition under which an operation of the device is enabled.
When the test condition is determined, a test zig appropriate to a corresponding sample is determined and the test is performed by connecting a power source for each test zig. That is, when it is desired to measure N sample, a plurality of power sources for operating the N samples, respectively, is necessary, and when the power sources do not have a measurement function, a separate measurement device corresponding to each power source is necessary.
The number and type of input terminals are changed according to the type of electronic device. In a case of a diode that is a 2-port device, one power source and one measurement device are demanded for one device, but in a case of a 3-port device, such as the BJT and the FET, two power sources and two measurement devices are demanded for one device. When the number of samples is increased, a configuration of a system demanded for the test becomes more complex, and costs are increased.
In order to have reliability of 95% or more during the reliability test, several hundreds of samples need to be tested, and a test zig for each sample, and a power source and a measurement device for driving each sample are demanded. During the test of a Radio Frequency (RF) device, the test is performed while applying an RF signal to each sample, so that a large number of expensive equipment is necessary.